I have recently upgraded to busybox v1.18.3 to v1.22.1 and seem to have discovered a bug in zcat.
I'm not entirely sure what the problem is, but files don't seem to be extracted correctly. The following procedure creates a basic filesytem image, gzips it on the host then scp's it to the target where zcat fails to properly extract it, while gunzip -c succeeds. It's very similar to my use-case and shows the issue. On the host: [jack@jackArch busybox-test]$ dd if=/dev/zero of=test.img bs=1MB count=100 100+0 records in 100+0 records out 100000000 bytes (100 MB) copied, 0.157787 s, 634 MB/s [jack@jackArch busybox-test]$ mkfs.ext3 test.img mke2fs 1.42.9 (28-Dec-2013) Allocating group tables: done Writing inode tables: done Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done [jack@jackArch busybox-test]$ sudo mount test.img /mnt/tmp [sudo] password for jack: [jack@jackArch busybox-test]$ ls -la /mnt/tmp total 17 drwxr-xr-x 3 root root 1024 Jun 12 17:14 . drwxr-xr-x 10 root root 4096 Jun 9 13:18 .. drwx------ 2 root root 12288 Jun 12 17:14 lost+found [jack@jackArch busybox-test]$ sudo umount /mnt/tmp [jack@jackArch busybox-test]$ dd if=test.img bs=1k | gzip -v9 > test-zcat 97656+1 records in 97656+1 records out 100000000 bytes (100 MB) copied, 0.574901 s, 174 MB/s 99.9% [jack@jackArch busybox-test]$ scp test-zcat [email protected]:/mnt/persist test-zcat 100% 108KB 108.5KB/s 00:00 On the target: target# pwd /mnt/persist target# ls -lah test-zcat -rw-r--r-- 1 root root 108.5K Jun 13 09:19 test-zcat target# time zcat test-zcat > test.img real 0m 0.00s user 0m 0.00s sys 0m 0.00s target# ls -lah test.img -rw-r--r-- 1 root root 108.5K Jun 13 09:20 test.img target# mount test.img /mnt/tmp/ mount: wrong fs type, bad option, bad superblock on /dev/loop4, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so. target# time gunzip -c test-zcat > test2.img real 0m 1.90s user 0m 1.31s sys 0m 0.58s target# ls -lah test2.img -rw-r--r-- 1 root root 95.4M Jun 13 09:21 test2.img target# mount test2.img /mnt/tmp/ target# ls -la /mnt/tmp/ drwxr-xr-x 3 root root 1024 Jun 12 16:14 . drwxr-xr-x 9 root root 4096 Jun 12 16:32 .. drwx------ 2 root root 12288 Jun 12 16:14 lost+found If you have any questions please let me know and I'll do my best to help. Regards, Jack -- Jack Mitchell ([email protected]) Embedded Systems Engineer Cambridgeshire, UK http://www.embed.me.uk -- _______________________________________________ busybox mailing list [email protected] http://lists.busybox.net/mailman/listinfo/busybox
